What's the "best" form of capital punishment?

Hopes&Fears answers questions with the help of people who know what they are talking about. Today we wondered, if the state insists on killing people, what's the "best" way to do it?
From tech bros to armed robbery,
what it’s like to deliver weed by bike in NYC
In the latest installment of our anonymous interview series, we spoke with three bike messengers who brave cops, robbers and inclement weather to deliver your weed.